asked on

simple cin/cout ?

I would like to read stdin until there is no more stdin, and then dump it to stdout.
Catch is: I must be able to do this with binary and ascii files, and I need to implement it with the stl.

(If this cannot be done with binaries - please let me know why. I have a feeling that because stdin is a text stream, that it won't work).

I am writing a pipe application.
I need to feed the pipe data to an out of process OLE server eventually.

Regards
-craig.

gcauthon

#include <stdio.h>

int main(void)
{
char data;
while(fread(&data,1,1,stdin)==1)
{
printf("%c",data);
}
return (0);
}

cmain

ASKER

I asked for an implementation using STL.
(Standard Template Library).

cmain

ASKER

I would also like to know the number of bytes that were piped into the application??

Thanks
-craig.

JYoungman

Why use the STL? Why not just use <iostream>?

JYoungman

#include <iostream>
int main()
{
unsigned char ch;
unsigned long count;
while ( (cin >> ch).good() )
{
++count;
cout << ch;
}
// optionally:-
cerr << "Transferred " << count << " bytes\n";
return 0;
}

cmain

ASKER

That works fine,
there is just one problem.

It stops at the first eof / non printable character.
I need to be able to pipe binary data. I want to use C++ io.
Your suggestion is fine except for the binary data problem.

nietod

I believe that a stream can be switched between binary and text mode. But I can't see how at the moment.

cmain

ASKER

I have here a sample program.
This actually works, sort of.
Call this application MYAPP

I can do the following.

cat MYFILE | MYAPP > NewFile.

The problem is that MYFILE is approximately 1300 bytes bigger than the resultant NewFile.

I know for a fact that my cat program works correctly.
I don't have source but...
cat MYFILE | cat > NewFile
results in an identical copy of MYFILE in NewFile,
which is what I want.

I am really getting confused here. I am trying to figure out what character is making the darn thing stop prematurely.
I have tried flushing cout with cout.flush(), but that doesn't help.

the two _setmode lines effectively change the streams to binary mode. I know this because otherwise the program stops after 78 bytes of a 65K file. With the _setmode I get about 64K of the 65K.

I don't really care if my final solution uses STL <iostream> or the standard C++ libraries <iostream.h>, but I don't want to use getc() unless I really have to (call me difficult if you want!)

#include <malloc.h>
#include <iostream>
#include <io.h>
#include <fcntl.h>
#include <wtypes.h>

void main ()
{
      using namespace std;
      TCHAR chr;
      _setmode( _fileno( stdin ), _O_BINARY );
      _setmode( _fileno( stdout ), _O_BINARY );
      while( (cin>>chr).good() )
            cout << chr;
      cout.flush();
      cerr << "done";
}

ASKER CERTIFIED SOLUTION

Bonev

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cmain

ASKER

Hey hey,
Thanks very much.

I was wondering if you perhaps know why the extraction operators cannot be used? read and write do work perfectly.

Thanks.
Regards
-craig.

Bonev

My personal opinion is that the operators are provided just for convenience.

alexo

Can't it be done with the STL copy() function and iostream iterators? That would look cleaner.